I had a very serious problem with many freezes and spontaneous reboots.  I 
wasn't sure if it was Ubuntu, or bad RAM, or something else.  It did 
improve over time -- instead of daily reboots I've been getting them more 
like weekly, or even biweekly.  I finally found out what it was:

https://community.amd.com/thread/225795

I have an AMD Ryzen 7 1700X.  This is a really nasty problem.  When I 
discovered this bug info yesterday, I went into the BIOS and disabled 
C-states.  That is supposed to help.  I assume Linux kernel updates have 
also been helping because it has improved a lot in the past year.  Maybe 
I'll be lucky and the nightmare will now be over.

Who should I be angry at?  AMD or the Linux kernel developers?  This was 
such a horror story that I think I might never buy another AMD chip.

Mike


On Sat, 21 Oct 2017, Mike Miller wrote:

> We discussed this a little back in July.  I just want to say that the syslog 
> wasn't helping much.  The crashes didn't seem to have much to do with what 
> was in the log.  I never figured out where the problem was, but as I said in 
> my previous message, over the past three months it kept on improving.  It 
> could go 3 days without a crash.  I have now upgraded to Ubuntu 17.10, and 
> I'm hoping that fixes more of my problems.  I was going to go back to 16.10 
> LTS, but that looked like it would be a big hassle, so I was crossing my 
> finger instead, just hoping it would fix itself (not as crazy as it sounds, 
> right?).
>
> Mike
>
>
> On Tue, 25 Jul 2017, Mike Miller wrote:
>
>> This was as serious as any BSOD.  I was using chromium-browser and
>> when I used the mouse to copy the URL, the whole system just froze.
>> The mouse still moved on the screen at first, but nothing else worked,
>> then the mouse froze too.  I doubt it had anything to do with
>> chromium.  I couldn't use ctrl-alt-F1 and the machine seemed to
>> disappear from the home network, so I couldn't even see it, never mind
>> ping it or ssh to it.
>> 
>> Here are the messages from /var/log/syslog (my machine is "taxa2"):
>> 
>> Jul 24 17:02:49 taxa2 org.gtk.vfs.Daemon[2445]: fusermount: failed to
>> access mountpoint /run/user/1000/gvfs: Permission denied
>> Jul 24 17:02:50 taxa2 hud-service[2166]: #033[31mvoid
>> DBusMenuImporter::slotGetLayoutFinished(QDBusPendingCallWatcher*)#033[0m:
>> "No such interface 'com.canonical.dbusmenu' on object at path
>> /org/ayatana/bamf/window/67108867"
>> Jul 24 17:02:54 taxa2 unity-panel-ser[2034]: menus_destroyed:
>> assertion 'IS_WINDOW_MENU(wm)' failed
>> 
>> That's what happened just as it got stuck.  There was nothing for 25
>> minutes before that and nothing after that until I reset the computer
>> and rebooted.
>> 
>> Any ideas?  Could it have anything to do with samba?  (That was
>> running, but nothing should have been accessing it at that time.)  I
>> was not using sshfs.
>> 
>> Mike
>> 
>